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The space-station program will seriously diminish the opportunities for advancing space science and technology if it proceeds as planned. Most national goals in space are better realized by robot spacecraft
Specific proteins regulate the growth of normal white blood cells and their differentiation into nondividing forms. Leukemic cells can also be made to differentiate, suggesting new approaches to cancer treatment
The plasma tall forms and disconnects from the comet in response to the solar wind and its magnetic field. Observations of comets Giacobini-Zinner and Halley may help to clarify such phenomena
"Time-reversed" light waves can be used to improve laser-beam quality, compensate for atmospheric turbulence, track a moving satellite, encode and decode messages and compare image patterns
Seawater circulating through fractured volcanic rock above sources of heat participates in chemical exchanges with the rock. A major result is significant deposits of metal, some now uplifted onto land
Some plant-produced chemicals poison herbivores or repel them; others reduce plants' nutritive value or impede an insect's growth. Herbivores in turn have ways of exploiting these natural products
The radioactive carbon 14 is isolated from the other atoms in a sample, making it possible to derive more accurate chronologies from much smaller archaeological or anthropological specimens
Tadpoles of the Cascades frog prefer to associate with siblings, which they distinguish from nonsiblings. The ability to recognize kin is not based on familiarity; it may have a genetic component